WordPress4 pagination

I am a newbie, I hope I can help each other to warm up to the newbies

Recently I am renovating wordpress, I wrote the code myself to make a paging
1, add the following css to the style.css under my theme

Js code

.pagination {
    width: auto;
    display: block;
    text-align: center;
    margin: 30px;
}
.pagination a {
    background-color: #eee;
    text-decoration: none;
    color: #999;
    font-size: 18px;
    padding: 0px 10px;
    line-height: 32px;
    height: 32px;
    margin: 0px 0.5px;
}
.pagination a.page-btn {
    width: 40px;
}
.pagination a.page-btn .icon-prev {
    position: absolute;
    width: 0px;
    height: 0px;
    border-top: 6px solid transparent;
    border-bottom: 6px solid transparent;
    border-left: 6px solid transparent;
    border-right: 6px solid transparent;
    border-left: none;
    border-right: 6px solid #999;
    left: 50%;
    margin-left: -3px;
    top: 50%;
    margin-top: -6px;
    -webkit-transition: all 0.1s ease;
    transition: all 0.1s ease;
}
.pagination a.page-btn .icon-next {
    position: absolute;
    width: 0px;
    height: 0px;
    border-top: 6px solid transparent;
    border-bottom: 6px solid transparent;
    border-left: 6px solid transparent;
    border-right: 6px solid transparent;
    border-right: none;
    border-left: 6px solid #999;
    left: 50%;
    margin-left: -3px;
    top: 50%;
    margin-top: -6px;
    -webkit-transition: all 0.1s ease;
    transition: all 0.1s ease;
}
.pagination a:hover {
    color: #fff;
}
.pagination a:hover .icon-prev {
    width: 0px;
    height: 0px;
    border-top: 6px solid transparent;
    border-bottom: 6px solid transparent;
    border-left: 6px solid transparent;
    border-right: 6px solid transparent;
    border-left: none;
    border-right: 6px solid #fff;
}
.pagination a:hover .icon-next {
    width: 0px;
    height: 0px;
    border-top: 6px solid transparent;
    border-bottom: 6px solid transparent;
    border-left: 6px solid transparent;
    border-right: 6px solid transparent;
    border-right: none;
    border-left: 6px solid #fff;
}
.pagination span {
    display: inline-block;
    margin: 0px 1px;
    color: #adadad;
    font-size: 18px;
}

2, Copy the following code into the functions.php of your own theme,

Php code

/**
/**
 * @param int $total_pages
 *  总页数
 * @param int $paged
 *  当前页数从1计
 * @param int $visible_count
 *  可见的页码数，接受自定义，如果自定义小于1或者大于max，置为max
 *
 *@author shandaiwang
 */
define('MAX_VISIBLE_PAGE_COUNT', 20);
function pagination($total_pages = 0, $current_page = 1, $visible_count = MAX_VISIBLE_PAGE_COUNT){
    // 入参适配
    if($total_pages <= 1) {
        return;
    }
    if($current_page <= 0) {
        $current_page = 1;
    }
    if($visible_count <= 0 || $visible_count > MAX_VISIBLE_PAGE_COUNT) {
        $visible_count = MAX_VISIBLE_PAGE_COUNT;
    }
    // 入参适配结束
    // 页码列表适配
    $range = ceil(($visible_count + 1) / 2);
    $start = $current_page - $range + 1;
    if($start < 1) {
        $start = 1;
    }
    $end = $start + $visible_count - 1;
    if ($end > $total_pages) {
        $end = $total_pages;
        // 向前反推，尽可能使显示个数为$visible_count
        $start = $end - $visible_count + 1;
        if($start < 1) {
            $start = 1;
        }
    }
    // 页码列表适配结束
    // 渲染
    echo "<div class=&#39;pagination&#39;>";
    if($current_page > 1) { // pre
        echo(&#39;<a href="&#39;.get_pagenum_link($current_page - 1).&#39;" class="common-btn page-btn"> <div class="icon-prev"></div></a>&#39;);
    }
    if($start != 1) {   // first[...]
        echo(&#39;<a href="&#39;.get_pagenum_link(1).&#39;" class="common-btn">1</a>&#39;);
        if ($start != 2) {
            echo(&#39;<span>...</span>&#39;);
        }
    }
    for ($i=$start; $i <= $end; $i++){  // list
        if ($i == $current_page) {
            echo(&#39;<a href="javascript:;" class="common-btn active">&#39;.$i.&#39;</a>&#39;);
        } else {
            echo(&#39;<a href="&#39;.get_pagenum_link($i).&#39;" class="common-btn">&#39;.$i.&#39;</a>&#39;);
        }
    }
    if($end < $total_pages) {   //[...]last
        if ($end + 1 < $total_pages) {
            echo(&#39;<span>...</span>&#39;);
        }
        echo(&#39;<a href="&#39;.get_pagenum_link($total_pages).&#39;" class="common-btn">&#39;.$total_pages.&#39;</a>&#39;);
    }
    if($current_page < $total_pages) { // next
        echo(&#39;<a href="&#39;.get_pagenum_link($current_page + 1).&#39;" class="common-btn page-btn"> <div class="icon-next"></div></a>&#39;);
    }
    echo "</div>\n";
}

3, just quote it where needed, in the form of

As for how to get $total_pages, $current_page, I The WP query used is in the shape of